Date of Award
Master of Science in Chemical Engineering - (M.S.)
Chemical Engineering and Chemistry
Leon Joseph Buteau
This study presents quantitative experimental data on the various stress-optical characteristics of polymer liquids, specifically, polyisobutylene. Through the use of a concentric cylinder rheogoniometer and a rotational viscometer, the temperature effects of a newtonian polyisobutylene liquid. was studied and was found to have a stress-optical coefficient independent of shear stress and minor temperature changes. The experiments confirm that the birefringence is a known function of the extinction angle and the shear stress. Various polyisobutylene liquids were used in a simple flow device to observe the birefringence in the 1-3 plane and the 2-3 plane. The results indicate that the 1-3 birefringence is proportional to the molecular weight of the material. Contrary to theory, birefringence effects are observed in the 2-3 plane. The study also included, the transient behavior of a highly non-newtonian polyisobutylene solution. The most notable aspect of this behavior was that of an 'overshoot' effect, whose occurence and magnitude is a function of the shear rate.
Biss, Russell B., "Rheo-optical properties of polyisobutylene" (1974). Theses. 2146.